Apparatus for the electrolytical treatment of ores or slimes.



No. 706,436. V Patented Aug. 5, I902. F. T. MUMFORD. APPARATUS FOR THEELEGTROLYTICAL TREATMENT OF URES 0R SLIMES] (Application filed Sept. 80,1901.)

(No Model.)

II. I

UNITED STATES PATENT OFFICE.

FRANK TOWNSEND MUMFORD, OF KALGOORLIE, WESTERN AUSTRALIA,

AUSTRALIA.

APPARATUS FOR THE ELECTROLYTICALTREATMENT OF ORES OR SLIMES.

SPECIFICATIG N formingpart of Letters Patent No. 706,436, dated August5, 1902.

Application filed September 30,1901. Serial No. 77,077, (No model.)

To all whom it. may concern;

Be it known that I, FRANK TOWNSEND MUM- FORD, metallurgist, ofKalgoorlie, Western the treatment by electrolysis of ores and slimes forthe extraction of precious metals, particularly gold, therefrom, wherebythe solution of the precious metals from the ore and its deposition areeffected by the aid of mercury in an easily-recoverable condition.

The apparatus is applicable for the treatment of any auriferous ore, butis especially valuablein the case of a slimy and clay-like ore or an orewhich requires Very fine crushmg. i

In order to obtain a rapid and complete precipitation of the gold from amercury cathode, it is necessary that the surface of the mercury shouldbe frequently renewed. By my invention I secure this essential result bypassing the cathode (which is composed of amalgamated copper plate orany other suitable metal) through or submerging itin a bath of mercury,as afterward described, and I thereby obtain an automatically andcontinuously renewed clean surface to act upon the precious metals, soresulting in a high or maximum degree of amalgamation.

The electrolyte may be a solution of cyanid of potassium or sodium,chlorid or bromid of sodium, or other suitable salt either jointly orseparately.

The construction of the apparatus for effooting the process is shown inthe accompanying drawings; but such construction is not arbitrary, as itmay be altered in detail Without departing from the vital features ofthis invention.

In the drawings, Figure 1 is a side View of the apparatus. Fig. 2 is anend view of same,

and Fig. 3 is a transverse section on line aa of Fig. 1.

-For the purpose of my invention I employ a cylinder A, made,preferably, of steel and lined on the inside with sheet-copper B andwhich may be electroplated for amalgamation purposes. The said lining isamalgamated,

and mercury is then poured into the cylinder,

thereby forming a continuous bath at the bottom of same. The bars 0,which constitute the anodes, are of carbon or iron and may be of anysection running the length of the cylinder and are supported by the endsD, as shown, and also at desired positions of their length, as by meansof the frame E, and such connections and anodes are suitably isolatedfrom the cylinder. The cylinder is provided with a manhole F and ismounted 011 rollers G and rotated by means of the spur-wheel H andsuitable gearing in the ordinary manner.

The cylinder is provided with a valve I, closing a port J for fillingand discharging purposes, and also with a plug-valve K for drawing offthe mercury and with an air-escape cock, as L. The body of mercury isshown in Fig. 3 by the letter M.

To work the apparatus, the cylinder is charged through the port J withcrushed ore and electrolyte and is then revolved slowly. The current isconveyed to the anode-bars O, which are connected outside the cylinderby a copper ring N, to which the current is conveyed by brushes or suchlike means. The electric current then passes through the pulp containingthe crushed ore, and the electrolyte, to which may be added a saltcapable under electrolysis of yielding oxygen or an oxidizing agent toaccelerate the solution of the gold or other precious metal, or a saltmay be added to lessen the resistanceof the electrolyte or to keep themercury at its maximum condition of efficiency. The pulp is kept inagitation by the revolving of the cylinder, the anodes acting asagitators to'break the pulp. If required, bars P, of wood or suitablematerial, may beplaced from end to end of the cylinder, so as to act asvanes for additional agitation. The anion generatedat the anode maydissolve the gold or other metal or it may be in a state of solutionpreviously to entering the cylinder, in any of which cases it isdeposited on the amalgamated lining of the cylinder, which is keptbright and in an efficient condition by being continuously submerged orpassed under the mercury-bath lying at the bottom of the cylinder. Anycoarse particles of gold would be immediately amalgamated by contact. Analkaline amalgam may also be formed which greatly facilitatesamalgamation.

Thefeed and discharge valve is placed in the cylinder end at a shortdistance from the copper lining of the cylinder, so as to allow mercuryto remain at the bottom while the slimes are being discharged. Whenfilling, the position is reversed, so that the port J would beat the topof the cylinder.

The pulp may be emptied into a settler, so as to settle and recover anymercury which it may contain.

The mercury is drawn off through the cock K, and which mercury may besqueezed and the amalgam then retorted.

. The amalgamated'lining can also be scraped for amalgam, entrance tothe cylinder being obtained through the manhole F.

The same apparatus as described may be made with a circular hole at thecenter of both cylinder ends, one hole beinglarger than the other. Thepulp containing the ore and the electrolyte may then be led in at thesmaller hole and allowed to flowthrough the cylinder and out at theother end, the cylinder being revolved all the time. Several cylindersof suitable size may be used in this way, the pulp passing from one tothe next in succession or by any other suitable arrangement, so as toobtain a continuous flow through the cylinders.

For example, a solution of cyanid of potassium containing soluble goldfrom percolation -vats might be passed through the cylinder in acontinuous stream, in which case the gold would be deposited on themercury cathode, as described previously.

Having thus described my said invention, what I'claim as new therein,and desire to secure by Letters Patent, is

1. An apparatus for the extraction of metals from their ores and slimes,comprising a metallic drum, a copper lining therein, means to maintainsaid lining continually amalgamated, a trailing electrical contact forthe drum, a plurality of conductive bars passing longitudinally throughthe drum and insulated therefrom, and means to rotate said drum,substantially as described.

2. An apparatus for the extraction of metals from their ores and slimes,comprising a rotatable cylindrical metallic drum, a copper liningtherein, a body of mercury in the drum to maintain the liningamalgamated, a valvecontrolled inlet and outlet, and a relief-valve atone end, a plurality of conductive rods insulated from and passinglongitudinally through the drum, a metallic ring connecting the bars,trailing electrical contact for the drum and one forsaid ring,substantially as described.

In testimony that I claim the foregoingas my invention I have signed myname in presence of two subscribing witnesses.

FRANK TOWNSEND MUMFORD.

Witnesses: I

W. BAIRD, HENRY A. JUDD.

